Electric insect destroyer



Jan. 31, 1933. l w, M- FROST 1,895,570

ELECTRIC INSEGT DESTROYER Filed Nov. 18. 195o 2 sheets-Shee 2 www Patented Jan. 3l, 1933 UNITED ATES 'WILLEM XF.. FROST, 0F SHOE, WASHUQ'GTN y ELECTRJIC NSECT DESTYER Application tiled November 18, 1930. `Serial No. 496,546.

My invention relates to electric insect destroyers, and particularly to the general type of such devices disclosed in my prior Fatent No. 974,785, 'November 8, 1910, and in 5 my copending application Serial No. 246,475.

ln devices of this type wires or other conductor elements are preferably arranged in spaced parallel relation upon a suitable support, alternate lengths or runs oi the wires being supplied with current ot diderent polarity and so positioned that a normally open circuit is completed through `adjacent wires by the body of an insect coming into contact with or close to the wires.

1t is important, in the use of such devices,

that the wires of opposite polarity be securely held in spaced parallel relation and that they be effectively insulated from each other. It is also desirable that the means employed for supporting and insulating the stretched wires be suciently compact to accommodate a row of spaced, alternately disposed wires by means of projections on opposite surfaces of the supporting member, and that the latter have suiiicient strength and rigidity to withstand the tension upon the stretched wires when assembled in operative position.

The wire-supporting and insulating means which l prefer for accomplishing these'results comprises a strip of porcelain or'other suitable dielectric material (e. g., wood, fiberboard, rubber or pyroxylin cut or molded to shape). ln my application Serial No. 246,- 47 5, l have shown and described Wire-supporting and insulating strips of such construction and conguration as will be calculated to meet the ordinary requirements of eompactness, strength and pleasing appear- 5 and insulating eectiveness of the wire-supporting strip by the production oit an insulating strip or member ot improved construction, and with regard also for greater convenience and lessened cost ci manufacture of screens or similar devices o dierent sizes through the use of standard lengths or unit sections of insulating strips adapted to be assembled in varyingnumbers and combinations to form suitable insulating strips of any desired length.

The exact nature of the invention and its objects and advantages will be apparent from the following specication and drawings, in which like numerals refer to like parts throughout the several views:

Figure 1 of the drawings is a front elevational View of an assembled electric insect destroyer in the` form of a window screen showing my improved form of wire-supportlng members.

Figure 2 is an enlarged perspective view, partly broken away, of one of the assembled wwe-supporting members shown in Figure 1.

Figure 3 is an enlarged sectional view taken on line 3-3vof Fig. 1. l

Figure 4 is a perspective view of one of the wire-supporting section units shown in F ig. 2.

Figures 5 and 6 are end elevational views of the unit shown in Fig. 4.

Figure 7 is a longitudinal sectional view taken on line 7 7 of Fig. 3

Figure 8- is a perspective view of a modified form of wire-supporting section unit.- U In Fig. 1 my present invention is shown mstalled in one of the several different forms of insect electrocuting devices to which it is applicable. As thus illustrated, the frame 1 embraces and holds in position a suitable number of umts 2, 3, 4, 5, and 2a.', 3a, da, and 5a to form a pair of wire-su porting members between which wires 6 and may be stretched in spaced parallel relation. The frame ma be 'of any suitable material, such as woo metal, or composition. lin the construction shown in the drawings the frame members 8, 9 lwhich hold the wire-supporting members are of sheet material, preferably metal, each hadvinga longiutdinal channellO open at one s1 e. A

The wire-sup orting units may be made of the same, or di erent lengths. Use of units of diderent lengths is preferable where they are intended to enter into the manufacture of screens of. different dimensions. A few zer and interchangeable sectional units, my imstandard lengthsof such units-(e. g., 1/2, 1, 2, and 21/2) will usually be suiiicient for ordinary manufacturing requirements, since, by the use of the proper combinations o units of these lengths, wire-supporting strips can be built up of any length ordinarily required in the manufacture oi insectelectrocuting screens Jfor doors and windows or other devices of the same general character but specilically different construction.

ln assembling the units they are placed end to end in the channel 1() of one of the frame members 8, 9, with the plain edge fn the channel and the serrated or wire-supporting edge projecting beyond the frame member. The units may be inserted in the 'frame member either by sliding them into the channel 10 'from its open end, or by opening the mouth or the channel and subsequently clamping the flanges 12 together when the units are in assembled position. To insure the retention of the units in the frame and increase the strength and rigidity of the assembled wire-supporting strips, each unit is provided on each side with a rib 13 along one of its longitudinal edges. These ribs furnish shoulders over which flanges 12 are seated to hold the ribbed edge of the unit in the channel 10. ln my preferred ,construction the flanges 12 seat in grooves formed between ribs 13 and additional ribs 31.

Upon the opposite edge of each wire-supporting member or strip, heads, ears, tongues or projections 14, 15 are provided for receiving and holding the parallel lengths or runs of the wires 6 and 7, the wire being turned or looped about the projections and held thereby in taut condition. These projections may be positioned upon either or both of the faces fof the wire-supportin strips or members and are preferably forme by molding the strip or the strip units into the configuration illustrated in the drawings.

Whether made integrally or of detachable proved wire-supporting member, as shown in the drawings, is of general I-beam configuration, one longitudinal edge being formed with a rib 13 and the other being cut or serrated to form a series or row of spaced wiresupporting heads, ears, tongues or projections 14, 15, respectively disposed in alternate relation upon the opposite sides or surfaces of the strip or strip unit. Transverse ribs ,16, 17, preferably of right-angled form, are

interposed between each adjacent pair of wire-supporting projections and combine therewith to define a vertical wire-receiving slot or groove 18 or 19 at each end of each projection 14 or 15. Each vertical slot is extended at an angle, as at 20 or 21, to undercut the adjacent head or projection 14 or 15. The angled grooves or slots 2O or 21, on opposite ends of each projection 14 or 15, converge` and, in conjunction with the depressed and corrugated web 22, deine the head or projection. The heads thus produced constitute tongues, lugs or projections adapted to be engaged by and to support return bends 23 o`- the wires 6 and 7.

These wire-supporting heads or projections are preferably provided upon each side oi the members or strips. The series oi angled slots 18-20 by which the heads or projections are deiined on one side of wiresupporting member or unit are staggered with respect to the similar slots 1Q-21 on the 4opposite side, and the ends of all of the slots (preferably countersnnlr, as 3), to provide air spaces around the wires in the slots, *for increased security against shortcircuiting between adjacent wires) are preferably arranged to lie in the same longitudinal plane approximately tare-ugh the middle o' 'the member or unit.

The web of each wire-supporting member or unit is 'formed with corrngetions providing depressions behind the heads or projections separated by generally trian nlar ribs or corrugations 24 lower ri s 16, 17. Ribs 16, 17', which extend to the edge o! the unit or strip, are oi' such height as to lie iiush at their outer end portion with the tops of heads or projections 14, 15 and at their opposite end with longitudinal rib 31 (as shown in Figs. 2 and 4) In the modiied form of construction illustrated in Fig. 8 transverse ribs 16 gradually decrease in height from the plane of the tops of heads or projections 14, 15 and merge into the lane of the web near the opposite edge of t e member or unit, preferably at points spaced from rib 13. 1

This manner of construction and contiguration produces a wire-supporting member or unit possessing the advantages of facility of production, and great strength, rigidity and holding power, holding bends or loops of wires in close parallel relation with unusual rmnes's and security. The strands or lengths of the wires 6 and 7, formed by looping the wires back and forth across the frame and engagin the loops in the inner ends of the slots andgbehind the heads or projections 14, 15, will lie in spaced parallel relation, all in the same plane. The bending of the wire loops over corrugations 24 tends to clamp or wedge the wire in the slots and pre- Vent its slipping, so that the wires are held securely in close parallel relation.

The wires 6, 7 thus form separate interlocking grids. One wire 6 is supported upon heads 14 on one side of the wire-supporting strips or units, while the other Wire 7 engages heads 15 upon the opposite side, the parallel lengths or runs of th twowires being in alternating arrangement and lying in a single plane to form a compound Grid of wires of opposite polarity. The heads or projections 14, 15 are so arranged and dimensioned that adjacent wires 6, 7 of opposite polarity will be suiciently close together to prevent insects from passing between them without bridging the gap in the circuit and thus being electrocuted.

Current may be supplied to the wires 6, 7 from any suitable source, preferably from the ordinary house-lighting circuit, through a suitable transformer' located either on the screen or in any other desired position, to the opposite poles of which the respective wires may be connected by suitable connectors. For example, the wires 6 and 7 may beelectrically connected at or near one end to binding posts 26 and 27, respectively, set into the eno unit of one of the assembled wire-supporting strips, or formed in a separate unit, and the other end of each wire secured in properly spaced grooves or slots 28, 29 forme in an extension 30 of the other end unit either integral therewith or made in the form of a separate wire-supporting unit.

lt claim:

l. An insulating wire-supporting member for an electric insect destroyer having a rib at one longitudinal edge, a series of spaced projections along the opposite longitudinal edge, and an intervening web portion having transverse ribs extending between adjacent projections and flush with said projections and said rib, the portions of the web between said transverse ribs-being depressed.

2. An insulating wire-supporting member for an electric insect destroyer having a row of spaced projections upon each of the op posite sides of said member along one longi` tudinal edge, a frame-engaging rib at its opposite longitudinal edge, and transverse ribs on each surface of said member Hush with said projections and extending between adjacent pairs of said projections, the surfaces kof said member between said transverse ribs being depressed and provided with transverse corrugations.

3. An insulating wire-supporting member for an electric insect destroyer comprising a strip having a series of projections along one longitudinal edge upon each side thereof, and a series-of transverse ribs on each side of said strip interposed between adjacent pairs of projections and separated therefrom by slots normal to the surfaces of the strip, said slots being arranged in pairs and bent into converging relation at their inner ends to undercut said projections, the projections, ribs and slots upon one side of said strip being odset relative to the projections, ribs and slots upon the opposite side thereof.

t. ln an electric insect destroyer, a frame including oppositely disposed insulating strips, each strip beingn formed of interchangeable units of dielectric material disposed` end to endv and having a row of projections along one longitudinal edge upon each side thereof, and a series of transverse ribs on each side of each strip interposed between adjacent pairs of said projections and separated therefrom by slots normal to the surfaces of the strip, said slots being arranged in pairs and bent into converging relation at their inner ends to undercut said proj ections, the projections upon one side of said strip being offset relative to the projections upon the opposite side thereof, and conducting wires supported in spaced parallel relation upon said projections, alternate lengths or runs of said wires to be supplied with current of opppsite polarity.

5. An electric insect destroyer comprising a'frame, insulating strips positioned on opposite sides of said frame, each of said strips having a substantially continuous rib along one longitudinal edge, and provided with a series of angled slots extending from said longitudinal edge through said rib and defining a series of wire-supporting projections, and wires engagedin the ends of said slots. y

6. A wire-supporting and insulating member for electric. insect destroyers having asubstantially continuous rib at one longitudinal edge and a series of angled slots extending from said longitudinal edge through said rib and defining a series of spaced aligned wire-supporting projections and intervening transverse ribs.

7. An insulating Wire-supporting member for an electric insect'destroyer having a row of spaced projections upon each of the opposite sides of said member along one longitudinal edge, a longitudinally grooved frameengaging rib upon each side of said member at its opposite longitudinal edge ortion, and transverse ribs on each side sur ace of said member lush with said projections and extending between adjacent pairs of said projections, the side surfaces of said member between said transverse ribs being depressed. 8. An insulating wire-supporting member for an electric insect destroyer having a rib upon each side surface along Aone longitudinal edge, and a serrated rib upon each side surface along the opposite longitudinal edge,

said serrated ribs being slotted to form a series of longitudinally spaced projections upon each side of said member, and transverse ribs on each side of said member lnterposed in the spaces between adjacent pairs of projections and separated therefrom by angled slots undercutting sald projections, the transverse ribs on each side of said member being flush with said projectlons and with the rib upon the opposite longitudinal edge of said member, andthe projections upon the opposite sides of said member Abeing staggered.

9. An insulating wire-supporting member A for an electric insect destroyer having a row of spaced projections upon each of the opposite sides of said'member along one longitudinal edge, a frame-engaging rib at its opposite longitudinal edge, and transverse ribs' on each surface of said member extending between adjacent pairs of said projections, the surfaces of said member between said transverse ribs being depressed and provided with transverse corrugations, said.

said projections and extending between adjacent pairs of said projections, and a conducting wire disposed 1n parallel reverse bends between said oppositcly disposed strips, with the bends engaged about said projections.

11. An insulating wire-supporting ber for an electric insect destroyer having af.- jacent one edge thereof a row of longitudinally spaced transverse slots arranged in pairs upon opposite sides thereof and the slots of each pair being oppositely inclined to define Wire-supporting projections, the end of each slot in one side of said member being substantially midway between the ends of a pair of slots inthe opposite side thereof, and

the slots of adjacent pairs of slots defining ribs having their top and end surfaces flush with said projections and extending transversely between adjacent projections.

12. An insulating wire-supporting mem- .ber for an electric insect destroyer having a row of spaced projections upon one side of said member and spaced ribs on the surface of said member Hush with said projections and extending between adjacent pairs of said projections.

13. An insulating wire-supporting member for an electric insect destroyer having a row of spaced projections upon each of the opposite sides of said member adjacent one longitudinal edge thereof, and spaced transverse ribs on each surface of said member extending between adjacent pairs 'of said projections, said ribs having their top and end surfaces flush with said projections.

14. An insulating Wire-supporting member for an electric insect destroyer having a row of spaced projections upon each of the opposite sides of said member along one 1ongitudinal ed e, and transverse ribs on each surface of said member flush with said projections and extending between adjacent pairs of said projections.

15. An insulating wire-supporting member for an electric insect destroyer having adjacent one edge thereof a row of longitudinally spaced slots arranged in pairs and thel larged.

WILLAM M.V FRUS'S. 

